1. Field of the Invention
The present invention relates generally to well drilling devices and, more particularly, to a mud pan used in combination with well drilling devices.
2. Description of the Prior Art
When drilling wells, for example a well for a water supply, a drill bit is rotatably driven into the ground in a generally vertical direction until a source of water is found. In order to remove the earth from the well hole during the drilling process, a slurry is typically pumped into the well hole so that, as the slurry is removed, it entrains the earth deposits that are removed by the drill during the drilling process.
Additionally, in order to prevent the well hole from collapsing on itself during the drilling process, the slurry typically contains a polymer or bentonite which congeals and prevents the collapse of the sides of the well hole. These polymers or bentonite are typically mixed with water so that a mixture of water and polymer and/or bentonite is pumped into and thereafter removed from the well hole.
The polymers and/or bentonite that are added to water to form the slurry are relatively expensive. Furthermore, the slurry laden with earth deposits as removed from the well hole during the drilling operation is typically recaptured or recycled and again pumped into the well hole.
In order to recapture or recycle the usable slurry that is pumped out of the well hole, the slurry that is pumped out of the well hole is fed into a mud pan which forms a reservoir. The heavier earth deposits sink to the bottom of the mud pan thus leaving a cleaner and a reusable slurry near the top of the reservoir formed by the mud pan. A pump inlet is then fluidly connected to the reservoir near its top so that relatively clean slurry can then be again pumped by the pump into the well hole in the desired fashion.
One disadvantage of these previously known mud pans, however, is that, during the well drilling operation, the mud pan reservoir begins to fill with earth deposits from the drilling operation. Previously, it has been necessary for a worker to continuously shovel the earth deposits from the bottom of the mud pan and onto the ground. This labor intensive operation increases the overall cost of the well drilling operation.